Nitric acid and distilled water with a little heat I've been dissolving silver contacts. Now I've run into a problem where the silver contacts simply do not want to dissolve. Heat more acid more water and nothing! I also double check just now one of the contacts which looks to not been melted much at all if any. I tested it with silver testing solution. And it was bright red indicating it is indeed silver. Could anyone tell me what the problem with this is? Am I just being impatient or are there some cases where the silver will not dissolve?